tsconfig.json extending from base tsconfig.json cannot override "declaration" to false

[benny-medflyt]

TypeScript Version: 2.4.1

If we have a "base" tsconfig.json file:

{
    "compilerOptions": {
        "declaration": true,
        "declarationDir": "./dist/types"
    }
}

And we try to create another tsconfig.json that extends it:

{
    "extends": "../base/tsconfig.json",
    "compilerOptions": {
        "declaration": false
    }
}

Then it doesn't work. We get error:

error TS5052: Option 'declarationDir' cannot be specified without specifying option 'declaration'.

There doesn't appear to be a way to "unset" the "declarationDir" setting. (Tried null, empty string, undefined)

[mhegazy]

looks like a duplicate of #16838 and #14184

[mhegazy]

Automatically closing this issue for housekeeping purposes. The issue labels indicate that it is unactionable at the moment or has already been addressed.